1. Field of the Invention
The present invention relates generally to devices for retaining flanged dental appliances in position. More particularly, the present invention relates to dentures having flexibly mounted flange extensions which aids in their retention and stabilization.
2. Description of the Prior Art
Presently, conventional dentures or the like, especially mandibular and distal extension partial dentures are predominantly designed to be placed over the gums, and generally rely on gravity, tooth clasps, and/or adhesives to retain and secure them in place. Various denture retaining devices are available in the prior art, but have up to now met with limited success. For instance, U.S. Pat. Nos. 1,924,265 and 1,947,026 to Wharton disclose three piece lower dentures wherein two side pieces extend lower than a middle piece. Upon placement in the mouth, the pieces are attached together through interlocking tongue and groove or other construction which allow movement in a vertical direction. Besides the relative difficulty in naneuvering the three pieces in the user's mouth, any sufficient force on the central piece of these dentures from incisor load may not be effectively transferred to the side pieces. This may lead to shear separation of the connections between the central piece and side pieces.
U.S. Pat. No. 3,919,771 to Ostermann discloses a device for retaining a lower denture having an externally attached fixed element, a retaining tongue which slides within the fixed element, and a cover piece which covers the fixed element and a portion of the retaining tongue. To use this device, the fixed element is secured to a lower denture such that the retaining tongue slides downward. After placement in the mouth, the user must slide the tongue below the mylohyoid ridge, then place the cover piece to secure the retaining tongue in position. Besides the necessity for complex user manipulation, this device applies pressure to the cavity below the mylohyoid ridge on a relatively small surface area. Further, the protruding structure of this device may lead to irritation and abrasion, thereby reducing the comfort with which the attached denture may be worn.
U.S. Pat. Nos. 4,376,629 to Ebeling and 4,923,795 to Franklin disclose flexible dentures which grip the gums of users. However, these dentures do not extend below the mylohyoid ridge or any other like bone ridges to provide support.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.